PondMaster Clarifier and Sterilizer Submersible 40-watt ultraviolet pond light for killing algae and bacteria Clarifies and sterilizes ponds up to 6,000 gallons; for use with pumps up to 3,000-gph 1.5 inch inlet and outlet for attaching flexible tubing 18-foot power cord Vortex flow design and slim diameter increases exposure to intense UV rays Measures 23-1/2 by 4 inches (length by width) submersed or above surface installation